The present invention relates to a sliver can transport carriage and a method for automatic sliver can exchange operations and, more particularly, to a sliver can transport carriage for supplying full sliver cans to the spinning stations of a spinning machine and transporting empty sliver cans from the spinning stations and a method for the supplying of full sliver cans.
U.S. Pat. No. 4,998,406 to Raasch discloses a sliver can transport carriage having a rotating table for supporting thereon a plurality of sliver cans in respective can supports. The can transport carriage transports a plurality of full sliver cans to a transfer position adjacent the spinning station of a spinning machine and the table rotates to sequentially bring each full sliver can supported on the can transport carriage into position for subsequent transfer to the spinning station. The can transport carriage receives empty sliver cans from the spinning station for subsequent transport of these empty sliver cans to a sliver can refill location.
Although the sliver can transport carriage disclosed in the Raasch '406 patent provides efficient transport of full sliver cans to the spinning stations of a spinning machine, the prior art transport carriage is probably best adapted to supply full sliver cans to those types of spinning stations having only a single row of sliver cans--e.g., each spinning station supports a single sliver can intermediately between the longitudinal edge of the spinning machine along which the transport carriage travels and the frame of the spinning station itself. However, in another known configuration of a spinning station of a textile spinning machine, each spinning station includes two rows of sliver cans--e.g., a first sliver can in a back row position and a second sliver can in a front row position laterally intermediate the first sliver can in the back row position and the longitudinal edge of the textile spinning machine. At a spinning station of this other known configuration, sliver may be continuously drawn from both sliver cans and factors such as differing start times and breakages almost invariably lead to a situation in which the sliver in one of the two sliver cans at a spinning station is fully drawn out from its respective sliver can before the other sliver has been fully drawn out from its respective sliver can.
In the event that the sliver can in the front row position has its sliver depleted first, a sliver can transport carriage such as the Raasch '406 transport carriage can efficiently exchange this empty sliver can for a full sliver can. However, if the sliver can in the back row position is depleted first while sliver continues to be drawn out of the other sliver can in the front row position, special arrangements must be made to access the empty sliver can in the back row position such as, for example, an arrangement in which a rotating table is provided at the spinning station to permit selective alternating movement of the sliver cans between the front and back row positions. Thus, the need exists for improvements in the methods for exchanging sliver cans at spinning stations of a textile spinning machine of the type having sliver cans in two or more rows. Also, the need exists for improvements in an apparatus for facilitating such sliver can exchange methods.